Dynamics related with the study of forces and torques and their effect on motion. It is the branch of physics (specifically classical mechanics). It is the opposite of kinematics. Kinematics studies the motion of objects without reference to its causes. 

Laws of Physics in everyday life

Simple Mechanical Devices

We can see physics in many places. One of them is a simple lever(like in a park). Levers come in three flavors, each of them has a different locations. They serve to magnify force, decreasing the weight of an object on the opposing end. A simple “see-saw” at a park consists of a lever (the locations for sitting) and the fulcrum (placed in the middle). The two opposing forces counter balance each other, creating a smooth ride through the air.

Transportation

The industry of transport is not a stranger to the manipulation of everyday physics. Cars and trains use the wheel, preventing gravity from slowing the movement of an object, allowing it to act as a constantly flowing object. Airplanes, allow lift as well as forward momentum. They manipulate physics by creating lift through wing shape as well as the wing’s angle – both of which serve to alter airflow.

Modern Communication

Physics is all relative with itself. This theme resonates through Einstein’s special and general theories of relativity. A focus is on the physics of time, which variesthroughout the universe and doesn’t retain a uniform structure; the speed of an object can order the time-flow of and on that object. A manipulation of this exists in GPS satellites. These satellites take into account variations in time-flow between the GPS receiver and the satellite.

Natural Applications

While you’re reading this sentence, physics isworking. Yeah… The eyes are evolved in many types . The ears hear sounds. Sounds occur through the alteration of molecules of air. Although, quantum physics exists within everything.  Every day, for example, plants break down sunlight and absorb water and carbon dioxide, making glucose and releasing oxygen.

GALILEO’S TEST.

Let’s turn back to Galileo. He was related mainly with a  form of acceleration, which occurs due to the gravity’s force. Aristotle had provided an explanation of gravity with his affirmation that objects fall to their “natural” position. Galileo set out to develop the first scientific explanation concerning how objects fall to the ground.

According to the predictions of Galileo, two metal balls of different sizes would fall with the same rate of acceleration. To test his hypotheses, he could not simply drop two balls from a rooftop and measure their rate of fall. Objects fall fast, and, he had to find another way to show the rate at which objects fell.

This he did by resorting to a method Aristotle: the use of mathematics as a means of modeling the behavior of objects. Since he couldn’t measure speed of object, he had to find an equation relating total distance to total time. Through a detailed series of steps, Galileo discovered that in uniform acceleration from rest there is a proportional relationship between distance and time.

With this mathematical model, Galileo, the scientist with a big fame could demonstrate uniform acceleration. He did this by using an experimental model: an inclined plane, down which he rolled a perfectly ball wich was round. This allowed him to extrapolate that in free fall, though velocity was greater, the same proportions still applied and therefore, acceleration was constant.

POINTING THE WAY TOWARD NEWTON.

The effects of system of Galileo were tremendous: he demonstrated mathematically that acceleration is constant, and established a method of hypothesis and experiment that became the basis of subsequent scientific investigation. He did not, however, attempt to calculate a figure for the acceleration of bodies in free fall; nor did he attempt to explain the overall principle of gravity, or indeed why objects move as they do—the focus of a subdiscipline known as dynamics.

At the end of Two New Sciences, Sagredo offered a strong prediction: “I really believe that… the principles which are set forth in this little treaty will, when taken up by minds, lead to another more outstanding result….” This prediction would come true with the job of a man who, because he lived in a somewhat more enlightened time was free to explore the implications of his physical studies without fear of intervention of Rome. Born in 1564  Galileo died in 1642, his name was Sir Isaac Newton.

NEWTON’S THREE LAWS OF MOTION.

In discussing the movement of the planets, Galileo had invented a term to describe the tendency of an object in motion to remain in motion, and an object at rest to remain at rest. The term was inertia.

Introduced by Newton in his Principia (1687), the three laws are:

First law of motion: An object at rest will remain at rest, and an object in motion will remain in motion, at a constant velocity unless or until outside forces act upon it.
Second law of motion: The net force acting upon an object is a product of its mass multiplied by its acceleration.
Third law of motion: When one object exerts a force on another, the second object exerts on the first a force equal in magnitude but opposite in direction.

These laws ended with Aristotle’s system. Instead of “natural” motion, Newton represented the concept of motion at a constant velocity—whether that velocity be a state of rest or of uniform motion. Actually, the closest thing to “natural” motion is the behavior of objects in outer space. There, without friction and far from the gravitational pull of Earth or other bodies, an object set in motion will remain in motion forever due to its own inertia. It follows from this watch, casually, that Newton’s laws were and are universal.

MASS AND GRAVITATIONAL ACCELERATION.

The first law establishes the principle of inertia, and the second law makes reference to the means by which inertia is measured: mass, or the resistance of an object to a change in its motion—including a change in velocity. Mass is one of the most fundamental notions in the world of physics, and it too is the subject of a popular misconception—one which confuses it with weight. In fact, weight is a force, equal to mass multiplied by the acceleration due to gravity.

It was Newton, through a complicated series of steps he explained in his Principia, who made possible the calculation of that acceleration—an act of quantification that had eluded Galileo. The figure most often used for gravitational acceleration at sea level is 32 ft (9.8 m) per second squared. This means that in the first second, an object falls at a velocity of 32 ft per second, but its velocity is also increasing at a rate of 32 ft per second per second. Hence, after 2 seconds, its velocity will be 64 ft (per second; after 3 seconds 96 ft per second, and so on.

Mass does not vary anywhere in the universe, whereas weight changes with any change in the gravitational field. When United States astronaut Neil Armstrong planted the American flag on the Moon in 1969, the flagpole (and indeed Armstrong himself) weighed much less than on Earth. Yet it would have required exactly the same amount of force to move the pole (or, again, Armstrong) from side to side as it would have on Earth, because their mass and therefore their inertia had not changed.